Apparatus for testing electric circuits



ELMENTHALER May 554M927.

APPARATUS FUR TESTING ELECTRIC CIRCUITS Filed Aug. 1.6, 1923 TTORNEY Patented ,May 24, 1927.

UNITED STATES WILLIAM EL'MENTHALER, OF CLEVELAND, OHIO.

APPARATUS FOR TESTING ELECTRIC CIRCUITS.

Application filed August 16, 1923. Serial No. 657,681.

My invention relates to testing apparatus which show whether an electric current is [lowing in a circuit into which the appara tus is inserted without affecting this circuit.

The main object of my invention is a simple and inexpensive but efficient apparatus for testing electric circuits, which does not interrupt the circuit or materially affect the same in any other manner, which has few parts, in which the parts themselves are simple and inexpensive, which provides ease of inspection and of repairs, which is readily adaptable for duplicate and mass production and therefore inexpensive and easy to secure repair parts, which does not get out of order easily, which can be installed in various positions and applied to various conditions without change thereof, and which can readily be modified to suit special conditions without material change of the main elements thereof. Other objects will ippear during the description of the apparatus shown in the accompanying drawing.

An apparatus and some modifications thereof, selected to illustrate my invention, are shown in the accompanying drawing in which Fig. 1 is ageneral perspective view of one type of testing apparatus embodying the features of my invention; Fig. 2 is a section, taken on a plane (vertical) indicated by the line 2-2 in Fig. 3, showing the details of Fig. '1 more clearly; Fig. 3 is a plan view of the bottom of the apparatus shown in Fig. 1, "taken as indicated at 3 in Fig. 1, and showing the armature mounting more clearly; Fig. 1 is a perspective view of a flat blank for the base of the apparatus; Fig. 5 is a perspective View of the fini'shed base shown up-sidedown for better illustration; Fig. 6 is a perspective view of a blank for the armature; Fig. 7 is a perspective view of the finished armature; Fig. 8 is afper'spect-ive view of a modified armature and a portion of a base; Fig. 9 is a perspective view of a testing apparatus similar to Fig. 1 but shows a modified washer.

Similar reference characters refer to simi lar parts throughout the views.

The apparatus shown in the drawing consists, principally, of the base A, the electromagnet "B, the Washer C, and the arn1ature D.

The base A. is here very economically formed of one piece 10 of fiat material (Fig. 4:),preferably a material which is non-magnetic, and is provided with the slits 11 and 12, the hinge-pin holes 13, the holes 1 1 for fastening screws, the opening 15 for the armature, and the threaded opening 16 for the armature core.

The portions 17 and 18, partially separated from the blank by the slits 11 and 12, are bent down to form hinge-ears hereinafter also designated as '17 and 18. The end 19 is also bent down, on the line aa, 1n the same direction as the ears 17 and 18, to form the supporting flange 19 by which the apparatus can be supported or suspended and which forms a confinement for the point of the armature. The words On and Off are stamped or otherwise provided on the base A adjacent to the opening 15 as shown. Fig. 5 shows the finished base but is there shown inverted for better illustration.

Instead of forming the flange 19 opposite to the hinge-ears 1'7 and 18 as seen in Fig. 5, this flange 19 may be formed at an angle to these ears as seen in Fig. 8.

The electro-magnet B is here very economicall-y formed of the screw 20, the spacer 21, and the solenoid or winding 22 in connection with the washer "C.

The screw has the head 23 at one end and is threaded at the other end to screw into the threaded opening 16 in the base A; this threadedend 24-. projects, below the bot tom of'the body 10 of the base A.

This screw 20 forms the main core of the electroqnagnet and is made of material which is magnetizable but which does not retain magnetism.

The spacer 21 forms a portion of the core for the electroanagnet, is also made of material which is magnetizable but which does not retain magnetism, surrounds the body of the screw 20, and extends, longitudinally, between the base A and the washer C The washer C is disposed between the head 23 and the upper end of the spacer 21 and may be formed flat with the holes 25 for support screws as seen in Fig. 1 or may have the flange 26 with the holes 27 for support-screws as seen in Fig. 9. This washer C can be rotated on the screw 20 so that either the holes 25 (Fig. 1) or the flange 26 with the holes 27 (Fig. 9) can be adjusted 'to different positions to suit mountingen various SHPPOI'tS. This washer may also be inverted as shown in dotted lines in Fig. 9 to further adapt the apparatus tor diflerent methods of mounting the same to a support.

The winding is disposed between the washer C and the base A as seen in Fig. 2 and is suitably insulated as is well. known in the art. The heads 28 and 29 ot' the winding 22 are adapted for insertion into an electric circuit.

\Vhen the screw is loosened, the washer C can be rotated into any desired position; after is tightened whereloy the entire apparatus is securely held together and can not easily come loose since such lightening firmly locks one end of the spacer21 to the base A and firmly locks the washer C between the head 23 and the other end of the spacer and firmly locks the spacer and the winding to the base A. The nut lock or other looking means may be provided to provide a more secure lock for the apparatus.

The armature D is here very economically formed of one piece ol. flat material which is magnetizable but which does not retain magnetism. This piece of material is first formed as a blank as shown in Fig. 6 with the portions 31 and 32 projecting sidewise at one end and with the hinge pin holes 33 therein and with the indicating point 34 on the other end. These portions 31 and 32 are then bent down on the lines 0 to form hingeears appropriate to the hinge-ears 17 and 18 of the base A. The finished armature is shown in Fig. 7. V 1

The hinge-pin 35 passes through all of the hinge-ears and com )letes the hinge joint between the base A and the armature.

In some instances it may be desirable to locate the indicating point otherwise than opposite the hinge joint as shown in Figs. 1 and 2. In such cases the flange 19 on the base A is modified to suit the new conditions as previously indicated during the description of the base and the armature is then modified to suit. In Fig. 8 is shown an armature having the indicating point 84 at an angle with the hinge joint to convey an idea as to how such conditions may be met.

In operation, when the winding 22 is inserted into a circuit by means of the leads 28 and 29, and when an electric current is flowing in this circuit, the core of the eleetro-magnet becomes magnetized as is usual in such apparatus and the armature will be attracted to the end '24 of the screw 21. Since thearmature is hinged to the base at one end and the middle portion thereof is attracted, the indicating point on the other end thereof moves upward a considerable distance although the middle portion of the armature may be spaced only a short distance from the end 24 when not attracted.

such position is reached, the screw 20- thereof slitted and sleeve, a

This comparatively large movement of the indicating point afl'ords an easy means of observing the action of this indicating point either by feeling, or by seeing, or by the words On and Off.

Vhen no electric current is flowing in this circuit, the armature auton'laticall y drops to off position due to its own weight; likewise when the current in this circuit is interrupted. A spring may, however, be employed to help the ari'nature into the off position in case the armature becomes somewhat magnetized or when the n])];)2l1:ll llS is installed upside down or sidcwise.

It is noted that the armature is neither included in nor affects the electric circuit and the current flowing in the s-tolenoid.

Modifications, other than those pointed out and shown, may be made, within the scope of the appended claims. 'lherefore, without limiting myself to the precise construction of the apl'iaratus and the arrangcment of the elements thereof as shown and described and to the particular construction of the elements as shown and described.

I claim I 1. An apparatus of the character described, including, a sleeve and a winding thereon, a base abutting one end of said sleeve, a washer abutting the other end of said sleeve, an armature supported on said base, a core having a head on one end thereof and threaded into said base at the other end thereof, and said washer and said base held against said sleeve by said head and the threaded engagement between said base and said core.

2. An apparatus of the character described, including, a base formed of a flat rectangular piece of material having one end the slitted portions bent down to form a pair of cars for supportin one end of an arn'iature, and the other end thereof. bent down and provided with an opening for confining-the other end of the armature.

3. An apparatus of the character described, including, a base formed of a flat rectangular piece of material having one end thereof slitted and the slitted portions bent down to form apair of ears, the other end of said piece of material bent down to form a flange and provided with an opening, an armatureformed of a flat piece of material having portions of one end thereof bent down to form a pair of cars adapted to the first mentioned pair of ears and the other end thereof formed with a point projecting through the opening in the flange of said base, and a hinge pin through both of said pairs of cars. I

4. An apparatus of the character described, including, a sleeve and a winding thereon, a core extending through said washer abutting one end of said sleeve and rotatable on said core, and said washer provided with means for supporting the apparatus.

5. An apparatus of the character described, including, a sleeve and a Winding thereon, a core extending through said sleeve and having a head on one end thereof, a washer on said core adjacent to said head and abutting one end of said sleeve and confining one end of the windin a base abutting the other end of said sleeve and confining the other end of the winding and threaded to the other end of said core, and an armature opposite said other end of the core and having one end thereof hinged to said base and the other end thereof projecting outside of said base.

6. An apparatus of the character decribed, including, a sleeve and a winding thereon, a core extending through said sleeve and having a head on one end thereof, a washer on said core adjacent to said head and abutting one end of said sleeve and confining one end of the winding, said washer having a flange to support the apparatus, a base abutting the other end of said sleeve and confining the other end of the winding and threaded to the other end of said core, said washer and said base held against said sleeve by said head and the threaded engagement bet-ween said base and said core, and an armature opposite the threaded end of said core and having one end thereof hinged to said base and the other end thereof projectlng outside of said base.

'7. An apparatus of the character described, including, a sleeve and a winding thereon, a core extending through said sleeve and having a head on one end thereof, a washer journaled on said core adjacent to said head and abutting one end of said sleeve and confining one end of the winding, said washer having a flange to support the apparatus, said flange reversible on said core, a base abutting the other end of said sleeve and confining the other end of the winding and threaded to "the other end of said core, said base having a flange with an opening through the same, said washer and said base held against said sleeve by said head and the threaded engagement between said base and said core, and an armature opposite the threaded end of said core and hav ing one end thereof hinged to said base and the other end thereof provided with a finger extending through the opening through said flange on the base.

8. An apparatus of the character described, including, a winding, a core within said winding, a washer against one end of said winding, said washer having means for supporting the apparatus, said washer journaled on said core, and said washer reversible on said core.

WILLIAM ELMENTHALER. 

